Certain firearms are equipped with mounting systems in the form of rails which generally running along the length of the barrel or elsewhere for mounting of accessories such as sighting scopes, lights, lasers or infrared sights. A MIL-STD-1913 rail is one type of standardized rail which has been adopted by the U.S. Department of Defense as a standardized mounting platform for use on the M16, M16A4 or 5.56 mm and AR-15 and other weapons platforms. The MIL-STD-1913 rail mounting system is also sometimes referred to as the “Picatinny” or “Weaver” rail. The same design of variations or facsimiles thereof are also used on imitation guns such as airsoft and toy gun products. As shown for example in FIGS. 1 and 5, a MIL-STD-1913 rail, denoted as “R” is formed by a series of spaced apart flanges “F” which have a generally T-shaped profile, with a central surface F1, lateral and outwardly angled surfaces F2, inwardly angled surfaces F3, and based surface F4 which extend from the rail body. Each of the flanges of a rail are spaced apart a distance of 0.206 inches (5.23 mm), i.e. slot width. The uniform spacing of the flanges of the rail provides a standardized mounting system for different types of accessories, and also function to dissipate some heat from the barrel so that the rail does not expand and contract with the barrel temperature. The spacing of the slot centers is 0.394 in (10.01 mm), and the slot depth is 0.118 in (3.00 mm). Other specifications and dimensions are set forth in MIL-STD-1913, incorporated herein by reference. Another type of standardized mounting rail is known as the Weaver rail, which has the same general configuration as the MIL-STD-1913 rail but with a slightly smaller slot width of 0.180 inches (4.572 mm). The MIL-STD-1913 or Picatinny or Weaver rails, also generally and collectively referred to herein as “rails” or “rail”, are generally disposed along the length of the barrel proximate to the breach, and are commonly arranged in tandem, for example on opposing sides of the barrel, or in a quadrant with one rail facing up, one down, one to the right and one to the left. The rails are formed integral with or otherwise attached to a mounting structure which is secured to the gun, such as to the exterior of the gun barrel. The rails are made of machined steel, aluminum, alloys or polymers and the edges of the flanges are hard and can injure or burn, and does not provide a comfortable or ergonomic grip for the forward non-trigger hand of the shooter.
Many different types of attachments and accessories have been developed for attachment to gun rails such as the MIL-STD-1913 rail, including aiming, telescopic, reflex and red dot sights, lights, lasers and laser sights and accompanying switches, forward hand grips, bipods and bayonets. These accessories are generally configured to fit or clamp over the cross-section of the rail and against the lateral edges of the flanges. Devices with wires, such as for example running from a switch to a light, present the challenge of wire management in trying to keep the wire or wires closely proximate to the rail. This is particularly important for combat and tactical users to avoid snagging of wires or other interference with the gun, although many of the current solutions still leave wires exposed and not closely secured to the rails. The different types of covers developed for attachment to the MIL-STD-1913/Picatinny and Weaver rails are made of hard plastic with a clip arrangement on the underside which snap-fits over the rail, and a hard outer surface. Although such rail covers provide a smoother surface for gripping the gun about the rails, they do not provide any improved or enhanced functionality, and rely solely on the strength of the plastic material to establish and maintain a firm grip on the rail. The hard plastic of such covers can be slippery, brittle, and does not perform any other function than to cover the flanges and slots of the rail and has minimal heat resistance.